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<h3 class="section" id="compatibility_005falias-1"><span>8.6 <code class="code">compatibility_alias</code><a class="copiable-link" href="#compatibility_005falias-1"> &para;</a></span></h3>

<p>The keyword <code class="code">@compatibility_alias</code> allows you to define a class name
as equivalent to another class name.  For example:
</p>
<div class="example smallexample">
<pre class="example-preformatted">@compatibility_alias WOApplication GSWApplication;
</pre></div>

<p>tells the compiler that each time it encounters <code class="code">WOApplication</code> as
a class name, it should replace it with <code class="code">GSWApplication</code> (that is,
<code class="code">WOApplication</code> is just an alias for <code class="code">GSWApplication</code>).
</p>
<p>There are some constraints on how this can be used&mdash;
</p>
<ul class="itemize mark-bullet">
<li><code class="code">WOApplication</code> (the alias) must not be an existing class;

</li><li><code class="code">GSWApplication</code> (the real class) must be an existing class.

</li></ul>

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